Hello there scubadave,
I've gotten in touch with Canon and have somethinga little different to try. At the very least the error should change.(Sorry, gallows humor). Please read this entire response before takingaction.
After the upcoming test procedure, I have included alink and procedure to contact Canon tech support. The assure me theywill replace any faulty tanks.
The purpose of this exercise iseither rule out ink tanks that are behaving or isolate the one(s)responsible for the dupliucate error. You should write down the results of thistest. Please perform the following:
1. Open the printer and remove all ink tanks.
2. Insert a single ink tank in the printer then close the cover.
3.Confirm whether the printer recognizes the installed tank properly. Ifit does, it will indicate it does not detect the other ink tanks, asthey are not currently installed in the printer.
4. Repeat steps 1-3 with another ink tank.
5.If the printer at any time indicates two of the same ink tanks areinstalled, the cause will be the last tank installed. For example, ifyou inserted an ink tank earlier, and you later inserted another inktank, and it said two of the same inks were installed, the cause of theissue is the last ink tank. Click here
for the Canon PIXMA iP4200 support page
Then click on e-mail support.
Fill out the form.
Under description, supply the following info:
Error- Duplicate Ink tank problem on my Canon PIXMA iP4200
<Describe how error occurs>
I have replaced the <color in> question> tank, reseated it, yet the error continues.
Youwill also need to list what inks are being used in the printer. Statethe type of ink that is being used and the order that the tanks areinstalled in the print head.
Provide the exact part number (such as BCI-6C, BCI3eBk, etc.) if possible.
The Canon support rep assured me they will be glad to replace the malfunctioning tank(s) for you at no cost. Please
respond with the test results, and specify the ink tank(s) that were not recognized correctly.
They responded quickly, professionally and apologetically. They want to help get this resolved for you.
I hope this helps end the frustration you must be feeling. If you need additional help or clarification, click the ASK button.
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